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Field Evaluation and In-Situ Stress-Testing of the Organic-Diffusive Gradients in Thin-Films Passive Sampler.

https://arctichealth.org/en/permalink/ahliterature295125
Source
Environ Sci Technol. 2018 Sep 24; :
Publication Type
Journal Article
Date
Sep-24-2018
Author
Jonathan K Challis
Kevin Stroski
Kim Luong
Mark L Hanson
Charles S Wong
Source
Environ Sci Technol. 2018 Sep 24; :
Date
Sep-24-2018
Language
English
Publication Type
Journal Article
Abstract
The organic-diffusive gradients in thin-films (o-DGT) technique has emerged as a promising aquatic passive sampler that addresses many of the challenges associated with current sampling tools used for measurement of polar organic contaminants. This study represents the first comprehensive field evaluation of the o-DGT in natural surface waters, across a wide suite of polar pharmaceuticals and pesticides. We explore the utility and limitations of o-DGT as a quantitative measurement tool compared to grab sampling and the polar organic chemical integrative sampler (POCIS) across four connected agricultural and wastewater-influenced freshwater systems spanning 600 km from the U.S. border to northern Manitoba, Canada. Overall, the suite of analytes detected with o-DGT and POCIS were similar. Concentrations in water estimated using o-DGT were greater than concentrations estimated from POCIS in 71 of 80 paired observations, and on average, the estimates from o-DGT were 2.3-fold higher than estimates from POCIS. Grab sample concentrations suggested that the systematic underestimation with POCIS were largely a result of sampling rate variation related to flow-rate and boundary-layer effects, an issue reported consistently in the POCIS literature. These comprehensive measurements in an agriculturally-influenced fast-flowing river, long-term sampling (>40 days) in a large dilute lake system, deployments in wastewaters, and under-ice at near-freezing temperatures represent effective stress-testing of o-DGT under representative and challenging conditions. Overall, its strong performance and improved accuracy over POCIS supports its use as a robust, quantitative, and sensitive measurement tool for polar organic chemicals in aquatic systems.
PubMed ID
30244575 View in PubMed
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Remodeling of Arctic char (Salvelinus alpinus) lipidome under a stimulated scenario of Arctic warming.

https://arctichealth.org/en/permalink/ahliterature311504
Source
Glob Chang Biol. 2021 Apr 10; :
Publication Type
Journal Article
Date
Apr-10-2021
Author
Chao Wang
Yufeng Gong
Fuchang Deng
Enmin Ding
Jie Tang
Garry Codling
Jonathan K Challis
Derek Green
Jing Wang
Qiliang Chen
Yuwei Xie
Shu Su
Zilin Yang
Jason Raine
Paul D Jones
Song Tang
John P Giesy
Author Affiliation
CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China.
Source
Glob Chang Biol. 2021 Apr 10; :
Date
Apr-10-2021
Language
English
Publication Type
Journal Article
Abstract
Arctic warming associated with global climate change poses a significant threat to populations of wildlife in the Arctic. Since lipids play a vital role in adaptation of organisms to variations in temperature, high-resolution mass spectrometry based lipidomics can provide insights into adaptive responses of organisms to a warmer environment in the Arctic and help to illustrate potential novel roles of lipids in the process of thermal adaption. In this study, we studied an ecologically and economically important species-Arctic char (Salvelinus alpinus), with a detailed multi-tissue analysis of the lipidome in response to chronic shifts in temperature by use of a validated lipidomics workflow. In addition, dynamic alterations in the hepatic lipidome during the time-course of shifts in temperature were also characterized. Our results showed that early life stages of Arctic char were more susceptible to variations in temperature. One-year-old Arctic char responded to chronic increases in temperature with coordinated regulation of lipids, including headgroup-specific remodeling of acyl chains in glycerophospholipids (GP) and extensive alterations in composition of lipids in membranes, such as less lyso-GPs, and more ether-GPs and sphingomyelin (SM). Glycerolipids (e.g., triacylglycerol, TG) also participated in adaptive responses of the lipidome of Arctic char. Eight-week-old Arctic char exhibited rapid adaptive alterations of the hepatic lipidome to stepwise decreases in temperature, while showing blunted responses to gradual increases in temperature, implying an inability to adapt rapidly to warmer environments. Three common PEs (PE 36:6
PE 16:1_20:5, PE 38:7
PE 16:1_22:6, and PE 40:7
PE 18:1_22:6) were finally identified as candidate lipid biomarkers for temperature shifts via machine learning approach. Overall, this work provides additional information to a better understanding of underlying regulatory mechanisms of the lipidome of Arctic organisms in the face of near-future warming.
PubMed ID
33837644 View in PubMed
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Wastewater sources of per- and polyfluorinated alkyl substances (PFAS) and pharmaceuticals in four Canadian Arctic communities.

https://arctichealth.org/en/permalink/ahliterature307903
Source
Sci Total Environ. 2020 Mar 15; 708:134494
Publication Type
Journal Article
Date
Mar-15-2020
Author
Kevin M Stroski
Kim Hoang Luong
Jonathan K Challis
Luis G Chaves-Barquero
Mark L Hanson
Charles S Wong
Author Affiliation
Richardson College for the Environment, University of Manitoba, Winnipeg, MB, Canada.
Source
Sci Total Environ. 2020 Mar 15; 708:134494
Date
Mar-15-2020
Language
English
Publication Type
Journal Article
Keywords
Arctic Regions
Environmental monitoring
Fluorocarbons
Nunavut
Waste Water
Water Pollutants, Chemical
Abstract
Effective removal of organic contaminants in wastewater effluent poses a challenge to small communities worldwide, particularly in the Arctic due to infrastructure challenges and harsh climates. To understand better the efficacy of current treatment options and risks posed by pharmaceuticals and pesticides on receiving waters in the Arctic, four representative human communities in Nunavut, Canada were evaluated. Per- and polyfluorinated alkyl substances (PFASs) were also investigated in one community. These communities have treatment ranging from primary lagoons, engineered wetlands, and natural lakes. Pharmaceuticals and pesticides were measured using the organic diffusive gradients in thin film (o-DGT) passive sampler in summer 2018. Of the 34 compounds studied, seven pharmaceuticals were found at least once: atenolol, carbamazepine, metoprolol, naproxen, sulfapyridine, sulfamethoxazole, and trimethoprim. With the exception of 5210?ng naproxen/L in Iqaluit, most receiving waters showed negligible amounts of contamination. Iqaluit had the poorest overall system performance while Baker Lake had the best. Measured pharmaceutical concentrations do not appear to pose a significant acute hazard to receiving waters at this time, based on known toxicological endpoints. PFAS concentrations were found to be over 100-fold greater in Cambridge Bay wastewater than previously reported Arctic seawater. Results suggest that wastewater may be an important point source of PFASs in Arctic communities. The o-DGT passive samplers performed well in marine Arctic settings. We recommend further testing of wastewater efficiencies in Arctic communities along with evaluations of seasonal variations.
PubMed ID
31791794 View in PubMed
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